A mask pattern of a conventional mask has different line density in respective regions, for example, line density of the mask pattern corresponding to scanning line in a fanout wiring region (which is consistent with a wiring density of a fanout wiring region) is usually relatively large (in other words, light transmissive gaps in the mask pattern is relatively small), while line density of the mask pattern corresponding to a pixel region is relatively small (in other words, the light transmissive gap in the mask pattern is relatively large). During the exposure, although exposure doses received by different regions of the mask are the same, yet the difference in the line density will cause difference in light transmittance in different regions (for example, in a region where the patterns are denser, the light transmittance is relatively low), so that the exposure dose required by the region with a larger line density is greater, and thus, it is difficult to ensure sizes after ideal exposure and development in different regions at the same time, which is not conducive to simplification of mask process.